Coeliac Disease

Presentations

• Bloating, abdo pain, diarrhoea or constipation, lethargy, weight loss, vitamin deficiencies (iron)

• Osteoporosis, infertility, recurrent miscarriage

• Extra-intestinal manifestations more common than intestinal

• 33% overweight/obese at time of diagnosis

• Neurological symptoms (ataxia, peripheral neuropathy, headache, depression, anxiety)

• Dermatitis herpetiformis (pruritic, blistering rash – pathognomonic)

• Unexplained elevated liver enzymes

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Investigations

• Endoscopic small bowel biopsy (gold standard) – requires ongoing gluten intake for 8 weeks before testing

• HLA types DQ2 and DQ8 – if negative, coeliac disease is excluded. If positive but asymptomatic, does not confirm the disease

• If HLA-positive → gluten challenge → proceed to gastroscopy ± biopsies

• Serology:

  • Total IgA and IgA tTG (best initial test)

  • If IgA deficient, use IgG-based tests (e.g., IgG deamidated gliadin peptide) to avoid false negatives

• Routine bloods to assess nutritional deficiencies:

  • FBC (anaemia), UEC, LFT

  • Iron studies, B12, folate, vitamin D, PTH

  • TFT (due to association with autoimmune thyroid disease)

  • BMD (bone mineral density) – at baseline and 2-yearly

• If dermatitis herpetiformis present, confirm with skin biopsy (direct immunofluorescence of perilesional skin)

• Consider small bowel imaging (MRI enterography) if suspecting refractory coeliac disease

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Management

• Education on the chronic nature of coeliac disease and lifelong gluten-free diet

• Strict gluten-free diet – even trace amounts cause intestinal damage

• Refer to:

  • Dietitian specialising in coeliac disease

  • Coeliac support groups

• Monitor for nutritional deficiencies – iron, folate, B12, vitamin D, calcium

• BMD scan 2-yearly – assess osteoporosis risk

• Assess for autoimmune conditions (T1DM, autoimmune thyroid disease, primary biliary cholangitis)

• Test first-degree relatives (up to 10% risk of coeliac disease in family members)

• Vaccination:

  • Ensure up-to-date pneumococcal and influenza vaccination (higher risk of hyposplenism)

  • Consider hepatitis B vaccination (higher risk of non-response due to immune dysfunction)

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Follow-up: Assessing Response to Gluten-Free Diet

• Gold standard: Histological improvement on repeat small bowel biopsy

• Serology: Anti-tTG levels decline but can take 12–24 months to normalise

• If persistent symptoms or no improvement in antibodies after 9–12 months:

  • Dietitian review (hidden gluten exposure)

  • Consider alternative diagnosis (microscopic colitis, SIBO, IBD, pancreatic insufficiency)

• If persistent villous atrophy despite adherence to diet: Consider refractory coeliac disease → refer to gastroenterologist

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Complications

• Malignancy:

  • Small bowel adenocarcinoma

  • Enteropathy-associated T-cell lymphoma (EATL) – risk x70 in coeliacs vs general population

  • Oesophageal SCC

• Nutritional deficiencies:

  • Iron deficiency anaemia, folate/B12 deficiency

  • Vitamin D deficiency → secondary hyperparathyroidism → osteoporosis

• Neurological complications:

  • Peripheral neuropathy

  • Gluten ataxia

• Refractory coeliac disease: Persistent symptoms despite strict gluten-free diet, associated with EATL

• Pancreatitis (increased risk)

• Hyposplenism – increased risk of infections (consider vaccinations)